Current-driven domain wall motion in thin ferromagnetic wires

S. E. Barnes; S. Maekawa

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Current-driven domain wall motion in thin ferromagnetic wires

S. E. Barnes·S. Maekawa

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Abstract

The coupling between a current and a Bloch wall is examined in the half-metal limit of the double exchange model. The conduction electrons transfer angular momentum to the Bloch wall with 100% efficiency in the absence of pinning. The wall is displaced without distortion with velocity proportional to the current. In the presence of a pinning potential either the angular momentum is destroyed by the perpendicular component of the anisotropy field or is converted to coherent magnons. A moving wall has its velocity reduced by pinning. The expression for the velocity agrees surprisingly well with experiment.

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S. E. Barnes, S. Maekawa. 2004-04-15. Current-driven domain wall motion in thin ferromagnetic wires. https://arxiv.org/abs/cond-mat/0311039

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